Power supply apparatus and method for manufacturing the same

ABSTRACT

A power supply apparatus includes: an enclosure in which a first accommodating part being in a trough shape and having a first opening surface is formed; and a first battery module which is in a column shape and in which a plurality of single battery cells are stacked. The first battery module  31  held in the first accommodating part by holding loads acting between a first end part and a second end part on two end sides in a stacking direction and a first inner wall part and a second inner wall part opposite to each other in the first accommodating part. In the first inner wall part and the second inner wall part, a first groove part and a second groove part communicating with the first opening surface and extending perpendicularly with respect to the first opening surface are formed respectively.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority of Japan patent application serial no. 2018-029830, filed on Feb. 22, 2018. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND Technical Field

The disclosure relates to a power supply apparatus. In particular, the disclosure relates to a power supply apparatus having a battery module in which a plurality of single battery cells are stacked.

Description of Related Art

Conventionally, a power supply apparatus mounted in a hybrid vehicle, an electric vehicle, etc., has a battery module in which a plurality of single battery cells are stacked. The battery module is configured by accommodating the single battery cells in a predetermined case, for example.

Here, performance improvement of the power supply apparatus is in demand, for example, improvement of volume energy density in the power supply apparatus is in demand. In order to improve the volume energy density in the power supply apparatus, the technique of directly accommodating the battery module in which the single battery cells are stacked in an enclosure is effective.

However, in the case in which the battery module in which the single battery cells are stacked is directly accommodated in an enclosure, the battery module needs to be accommodated in a state in which there is no gap in the accommodating part in the enclosure and the battery module is fixed by a reaction force (holding load) from the wall part of the accommodating part.

Regarding this, for example, a technique is disclosed to stack battery cells and insert the stacked battery cells into a storing part in a state of being compressed in the stacking direction (see, for example, Patent Document 1: Japanese Laid-Open No. 2017-111893).

However, even though Patent Document 1 discloses the technique of inserting stacked battery cells into the accommodating part in the state of being compressed in the stacking direction, Patent Document 1 does not disclose a specific method in the manufacturing process, the structures of various parts suitable for the method, etc.

In particular, manufacturing robots, etc., are used in actual manufacturing, and technical development relating to the above-mentioned method carried out by the manufacturing robots etc. and the structures of various parts suitable for the method is in demand.

SUMMARY

A power supply apparatus according to an embodiment of the disclosure includes: an enclosure in which an accommodating part being in a trough shape and having an opening surface is formed; and a battery module which is in a column shape and in which a plurality of single battery cells are stacked. The battery module is held in the accommodating part by holding loads acting between a first end part and a second end part on two end sides in a stacking direction and a first inner wall part and a second inner wall part opposite to each other in the accommodating part. In the first inner wall part and the second inner wall part, a first groove part and a second groove part communicating with the opening surface, extending perpendicularly with respect to the opening surface, and having a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction are formed respectively.

A manufacturing method according to an embodiment of the disclosure is a method for manufacturing a power supply apparatus. The power supply apparatus includes: an enclosure in which an accommodating part being in a trough shape and having an opening surface is formed; and a battery module which is in a column shape and in which a plurality of single battery cells are stacked. The battery module is held in the accommodating part by holding loads acting between a first end part and a second end part on two end sides in a stacking direction and a first inner wall part and a second inner wall part opposite to each other in the accommodating part. In the first inner wall part and the second inner wall part, a first groove part and a second groove part communicating with the opening surface, extending perpendicularly with respect to the opening surface, and having a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction are formed respectively. The method includes: clamping the battery module by using a first arm part and a second arm part, and gripping the battery module while applying a pre-pressure force along the stacking direction to the first end part and the second end part; inserting the first arm part and the second arm part into the first groove part and the second groove part from the opening surface side in a state in which the battery module is gripped by using the first arm part and the second arm part; and withdrawing the first arm part and the second arm part from the first groove part and the second groove part after removing the pre-pressure force applied by the first arm part and the second arm part.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view explaining a configuration in a power supply apparatus of the disclosure.

FIG. 2 is a perspective view explaining the configuration in the power supply apparatus of the disclosure.

FIG. 3A is an enlarged view of a region A in FIG. 1.

FIG. 3B is a partial enlarged view of a II-II section in FIG. 2, in which a battery module is accommodated in an accommodating part.

FIG. 4 is a view showing an installation example of a cell voltage sensor unit which is one of the members connected to a battery module.

FIG. 5A is a view showing a state in which a first arm part and a second arm part apply a pre-pressure force while gripping a battery module.

FIG. 5B is a view showing a state in which the first arm part and the second arm part are inserted into a first groove part and a second groove part from an opening surface side while gripping the battery module.

FIG. 5C is a view showing a state in which the pre-pressure force applied by the first arm part and the second arm part is removed.

FIG. 5D is a view showing a state in which rotational driving and the pre-pressure force of the first arm part are removed.

FIG. 5E is a view showing a state in which the first arm part and the second arm part are withdrawn from the first groove part and the second groove part.

FIG. 5F is a diagram showing a procedure of connecting a cell voltage sensor unit to a first battery module.

DESCRIPTION OF THE EMBODIMENTS

The disclosure relates to a power supply apparatus having an accommodating part suitable for accommodating a battery module in which a plurality of single battery cells are stacked in a state of being compressed in a stacking direction, and a method for manufacturing the power supply apparatus.

(1) A power supply apparatus (e.g., a power supply apparatus 1 described later) according to an embodiment of the disclosure includes: an enclosure (e.g., an enclosure 10 described later) in which an accommodating part (e.g., a first accommodating part 11, a second accommodating part 12, a third accommodating part 13, and a fourth accommodating part 14 described later) being in a trough shape and having an opening surface (e.g., a first opening surface 16, a second opening surface 17, a third opening surface 18, and a fourth opening surface 19 described later) is formed; and a battery module (e.g., a first battery module 31, a second battery module 32, a third battery module 33, and a fourth battery module 34 described later) which is in a column shape and in which a plurality of single battery cells (e.g., single battery cells 40 described later) are stacked. The battery module is held in the accommodating part by holding loads acting between a first end part (e.g., first end parts 31 a, 32 a, 33 a, 33 a described later) and a second end part (e.g., second end parts 31 b, 32 b, 33 b, 34 b described later) on two end sides in a stacking direction (e.g., a stacking direction X described later) and a first inner wall part (e.g., first inner wall parts 11 a, 12 a, 13 a, 14 a) and a second inner wall part (e.g., second inner wall parts 11 b, 12 b, 13 b, 14 b described later) opposite to each other in the accommodating part. In the first inner wall part and the second inner wall part, a first groove part (e.g., first groove parts 21, 23, 25, 27 described later) and a second groove part (e.g., second groove parts 22, 24, 26, 28 described later) communicating with the opening surface, extending perpendicularly with respect to the opening surface, and having a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction are formed respectively.

(2) According to an embodiment of the disclosure, the first groove part and the second groove part extend from the opening surface to a bottom surface (e.g., a bottom surface 11 e described later) of the accommodating part.

(3) According to an embodiment of the disclosure, the battery module is provided in the accommodating part, such that two electrodes of each of the single battery cells are arranged in rows along the stacking direction in a plan view, and the first groove part and the second groove part are formed between two rows of the electrodes in the plan view.

(4) According to an embodiment of the disclosure, at least one of the first groove part and the second groove part is provided with a member connected to the battery module.

(5) A manufacturing method according to an embodiment of the disclosure is a method for manufacturing a power supply apparatus (e.g., a power supply apparatus 1 described later). The power supply apparatus includes: an enclosure (e.g., an enclosure 10 described later) in which an accommodating part (e.g., a first accommodating part 11, a second accommodating part 12, a third accommodating part 13, and a fourth accommodating part 14 described later) being in a trough shape and having an opening surface (e.g., a first opening surface 16, a second opening surface 17, a third opening surface 18, and a fourth opening surface 19 described later) is formed; and a battery module (e.g., a first battery module 31, a second battery module 32, a third battery module 33, and a fourth battery module 34 described later) which is in a column shape and in which a plurality of single battery cells (e.g., single battery cells 40 described later) are stacked. The battery module is held in the accommodating part by holding loads acting between a first end part (e.g., first end parts 31 a, 32 a, 33 a, 33 a described later) and a second end part (e.g., second end parts 31 b, 32 b, 33 b, 34 b described later) on two end sides in a stacking direction (e.g., a stacking direction X described later) and a first inner wall part (e.g., first inner wall parts 11 a, 12 a, 13 a, 14 a) and a second inner wall part (e.g., second inner wall parts 11 b, 12 b, 13 b, 14 b described later) opposite to each other in the accommodating part. In the first inner wall part and the second inner wall part, a first groove part (e.g., first groove parts 21, 23, 25, 27 described later) and a second groove part (e.g., second groove parts 22, 24, 26, 28 described later) communicating with the opening surface, extending perpendicularly with respect to the opening surface, and having a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction are formed respectively. The method includes: clamping the battery module by using a first arm part (e.g., a first arm part 110 described alter) and a second arm part (e.g., a second arm part 120 described later), and gripping the battery module while applying a pre-pressure force along the stacking direction to the first end part and the second end part; inserting the first arm part and the second arm part into the first groove part and the second groove part from the opening surface side in a state in which the battery module is gripped by using the first arm part and the second arm part; and withdrawing the first arm part and the second arm part from the first groove part and the second groove part after removing the pre-pressure force applied by the first arm part and the second arm part.

(6) According to an embodiment of the disclosure, the method further includes providing a member connected to the battery module in at least one of the first groove part and the second groove part after withdrawing the first arm part and the second arm part from the first groove part and the second groove part.

(1) The power supply apparatus of the disclosure includes the enclosure in which the accommodating part being in a trough shape and having the opening surface is formed, and the battery module held in the accommodating part. In the first inner wall part and the second inner wall part on the two end sides in the stacking direction of the battery module in the accommodating part of the enclosure, the first groove part and the second groove part which communicate with the opening surface, extend perpendicularly with respect to the opening surface, and have a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction are formed. Also, due to the holding loads acting between the first end part and the second end part on the two end sides in the stacking direction and the first inner wall part and the second inner wall part, the battery module is held in the accommodating part. According to the power supply apparatus of the disclosure, the battery module can be mounted directly in the accommodating part of the enclosure in a state of being compressed along the stacking direction without using a holder, etc., for applying a load to the battery module along the stacking direction. In order to mount the battery module in the accommodating part as described above, it is necessary to use the arms provided on the two end sides in the stacking direction of the battery module, and accommodate the battery module together with the arms in the accommodating part while applying the pre-pressure force along the stacking direction. With respect to this, according to the power supply apparatus of the disclosure, the first groove part and the second groove part formed in the first inner wall part and the second inner wall part serve as escape grooves of the arms, so the battery module can be mounted directly in the accommodating part of the enclosure in the state of being compressed along the stacking direction.

(2) In the power supply apparatus of the disclosure, the first groove part and the second groove part extend from the opening surface to the bottom surface of the accommodating part. Therefore, according to the power supply apparatus of the disclosure, the escape grooves of the arms can be secured from the opening surface to the bottom surface of the accommodating part. Hence, according to the power supply apparatus of the disclosure, the pre-pressure force applied to the battery module can be uniform because the arms extending from the upper surface to the lower surface of the battery module can be used when the pre-pressure force is applied along the stacking direction of the battery module.

(3) In the power supply apparatus of the disclosure, the battery module is provided in the accommodating part, so that the two electrodes of each of the single battery cells are arranged in rows along the stacking direction in a plan view, and the first groove part and the second groove part are formed between the two rows of electrodes in a plan view. Therefore, in the battery module accommodated in the accommodating part, since the loads along the stacking direction can be applied to the two electrodes, which are portions where the first groove part and the second groove part are not formed, the occurrence of troubles in the respective electrodes of the battery module during charge and discharge can be suppressed.

(4) In the battery module formed by stacking the single battery cells, various members such as a bus bar connecting the electrodes of each of the single battery cells and a cell voltage sensor unit for detecting the cell voltage of each of the single battery cells are connected. Therefore, a space for providing the members connected with these battery modules needs to be secured in the enclosure. Regarding this, in the power supply apparatus of the disclosure, the member connected to the battery module is provided in at least one of the first groove part and the second groove part serving as the escape grooves of the arms when the battery module is accommodated in the accommodating part. Therefore, according to the disclosure, the volume of enclosure can be reduced.

(5) The method for manufacturing the power supply apparatus of the disclosure includes: clamping the battery module by using a first arm part and a second arm part, and gripping the battery module while applying a pre-pressure force along the stacking direction to the first end part and the second end part of the battery module; inserting the first arm part and the second arm part into the first groove part and the second groove part from the opening surface side in a state in which the battery module is gripped by using the first arm part and the second arm part; and withdrawing the first arm part and the second arm part from the first groove part and the second groove part after removing the pre-pressure force applied by the first arm part and the second arm part. According to the method for manufacturing the power supply apparatus of the disclosure, the first groove part and the second groove part formed in the first inner wall part and the second inner wall part serve as the escape grooves of the first arm part and the second arm part, and the battery module can be mounted directly in the accommodating part of the enclosure in the state of being compressed along the stacking direction.

(6) According to the method for manufacturing the power supply apparatus of the disclosure, a member connected to the battery module is provided in at least one of the first groove part and the second groove part after the first arm part and the second arm part are withdrawn from the first groove part and the second groove part. Therefore, the volume of the enclosure can be reduced.

Embodiments of the disclosure are described below with reference to the drawings. The configuration in a power supply apparatus 1 of this embodiment will be described with reference to FIGS. 1 to 3B. FIG. 1 is a plan view illustrating the configuration of the power supply apparatus 1. FIG. 2 is a perspective view explaining the configuration in the power supply apparatus. FIG. 3A is an enlarged view of a region A in FIG. 1, and FIG. 3B is a partial enlarged view of a II-II section in FIG. 2, in which a battery module is accommodated in an accommodating part.

First, the power supply apparatus 1 in this embodiment will be described schematically. As shown in FIG. 1 and FIG. 2, the power supply apparatus 1 includes an enclosure 10, a first battery module 31, a second battery module 32, a third battery module 33, and a fourth battery module 34 that are directly accommodated in the enclosure 10, and a power control part 39 accommodated in the enclosure 10. The power supply apparatus 1 is mounted in an electric vehicle (not shown) which travels by adopting the power supply apparatus 1 as a power source and driving the motor in a state in which a lid part (not shown) is attached to an opening side of the enclosure 10.

Each of the first battery module 31, the second battery module 32, the third battery module 33, and the fourth battery module 34 is a battery module in a column shape, more specifically, a square column shape, formed by stacking a plurality of single battery cells 40. Hereinafter, the direction in which the single battery cells 40 are stacked is referred to as a stacking direction X.

In addition, the enclosure 10 includes a first accommodating part 11 that is in a trough shape and has a first opening surface 16 in a rectangular shape in a plan view, a second accommodating part 12 that is in a trough shape and has a second opening surface 17 in a rectangular shape in a plan view, a third accommodating part 13 that is in a trough shape and has a rectangular third opening surface 18 in a rectangular shape in a plan view, a fourth accommodating part 14 that is in a trough shape and has a fourth opening surface 19 in a rectangular shape in a plan view, and a fifth accommodating part 15 that is in a trough shape. The power control part 39 is accommodated in the fifth accommodating part 15.

The first battery module 31 is inserted from the first opening surface 16 in a pre-pressured state in the stacking direction, and is held in the first accommodating part 11 by holding loads acting between a first and end part 31 a and a second end part 31 b on two end sides in the stacking direction X and a first inner wall part 11 a and a second inner wall part 11 b opposite to each other in the first accommodating part 11.

Likewise, the second battery module 32 is inserted from the second opening surface 17 in the pre-pressured state in the stacking direction, and is held in the second accommodating part 12 by holding loads acting between a first end part 32 a and a second end part 32 b on two end sides in the stacking direction X and a first inner wall part 12 a and a second wall part 12 b opposite to each other in the second accommodating part 12.

Likewise, the third battery module 33 is inserted from the third opening surface 18 in the pre-pressured state in the stacking direction, and is held in the third accommodating part 13 by holding loads acting between a first end part 33 a and a second end part 33 b on two end sides in the stacking direction X and a first inner wall part 13 a and a second wall part 13 b opposite to each other in the third accommodating part 13.

Likewise, the fourth battery module 34 is inserted from the fourth opening surface 19 in the pre-pressured state in the stacking direction, and is held in the fourth accommodating part 14 by holding loads acting between a first end part 34 a and a second end part 34 b on two end sides in the stacking direction X and a first inner wall part 14 a and a second wall part 14 b opposite to each other in the fourth accommodating part 14.

Here, each accommodating part has a first groove part and a second groove part respectively formed in the first inner wall part and the second inner wall part. Specifically, the first accommodating part 11 has a first groove part 21 formed in the first inner wall part 11 a and a second groove part 22 formed in the second inner wall part 11 b. The second accommodating part 12 has a first groove part 23 formed in the first inner wall part 12 a and a second groove part 24 formed in the second inner wall part 12 b. The third accommodating part 13 has a first groove part 25 formed in the first inner wall part 13 a and a second groove part 26 formed in the second inner wall part 13 b. The fourth accommodating part 14 has a first groove part 27 formed in the first inner wall part 14 a and a second groove part 28 formed in the second inner wall part 14 b.

The first groove part and the second groove part described above are parts into and from which a first grip part 115 of a first arm part 110 and a second grip part 125 of a second arm part 120 in a manufacturing robot 100 to be described later are inserted and removed. In detail, the first groove part and the second groove part are parts into which the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120 gripping the battery module in the pre-pressured state to be compressed in the stacking direction are inserted and from which the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120 having removed the pre-pressure to the battery module are withdrawn.

Subsequently, the power supply apparatus 1 in this embodiment will be described in detail. Here, in the following description, the configurations, relationships, etc. of the first battery module 31 and the first accommodating part 11 will be described, and the descriptions of other battery modules and other accommodating parts will be omitted. For other battery modules and other accommodating parts, the descriptions about the first battery module 31 and the first accommodating part 11 also apply.

Referring to FIGS. 1 to 3B, the power supply apparatus 1 has the first accommodating part 11 formed in the enclosure 10 and the first battery module 31 directly accommodated in the first accommodating part 11.

The first battery module 31 is a battery module which is in a square column shape and formed by stacking the single battery cells 40. Each of the single battery cells 40 has a first electrode 41 and a second electrode 42. The first battery module 31 is accommodated in the first accommodating part 11, so that the two electrodes 41 and 42 of each of the single battery cells 40 are arranged in rows along the stacking direction X in a plan view perpendicular to the first opening surface 16.

The first electrode 41 is an electrode arranged on a side in a width direction Y (see FIG. 3A) orthogonal to the stacking direction X. The first electrodes 41 of the respective single battery cells 40 are arranged side by side along the stacking direction X on the side in the width direction Y. The first electrodes 41 arranged side by side in the stacking direction X are arranged side by side as positive and negative electrodes alternately in the stacking direction X. In addition, a positive electrode and a negative electrode that are adjacent are electrically connected by a bus bar (not shown).

The second electrode 42 is an electrode arranged on the other side in the width direction Y (see FIG. 3A) orthogonal to the stacking direction X. The second electrodes 42 of the respective single battery cells 40 are arranged side by side along the stacking direction X on the other side of the width direction Y. Similarly, the second electrodes 42 arranged side by side in the stacking direction X are arranged side by side as positive and negative electrodes alternately in the stacking direction X. In addition, a positive electrode and a negative electrode that are adjacent are electrically connected by a bus bar (not shown).

Moreover, the first battery module 31 is inserted from the first opening surface 16 in the pre-pressured state in the stacking direction X, and is held in the first accommodating part 11 by the holding loads acting between the first end part 31 a and the second end part 31 b on the two end sides in the stacking direction X and the first inner wall part 11 a and the second inner wall part 11 b opposite to each other in the first accommodating part 11.

In detail, the first battery module 31 is inserted from the first opening surface 16 into the first accommodating part 11 in the pre-pressured state to be compressed in the stacking direction X. In addition, the first battery module 31 is directly accommodated in the first accommodating part 11. The first battery module 31 is held in the first accommodating part by a holding load generated between the first end part 31 a on one of the end sides in the stacking direction X and the first inner wall part 11 a of the accommodating part 11 and a holding load generated between the second end part 31 b on the other end side of the stacking direction X and the second inner wall part 11 b of the accommodating part 11. The first battery module 31 is held in a compressed state in the first accommodating part 11 by the holding loads from the first inner wall part 11 a and the second inner wall part 11 b.

Subsequently, as shown in FIGS. 1 to 3B, the first accommodating part 11 is a trough-shaped accommodating part having the first opening surface 16. The first accommodating part 11 has the first opening surface 16, the first inner wall part 11 a on one of the sides in the stacking direction X, the second inner wall part 11 b on the other side in the stacking direction X, a third inner wall part 11 c on one of the sides in the width direction Y, a fourth inner wall part 11 d on the other side in the width direction Y, and a bottom surface 11 e opposite to the first opening surface 16.

In addition, the first accommodating part 11 has the first groove part 21 formed in the first inner wall part 11 a and the second groove part 22 formed in the second inner wall part 11 b. The first groove part 21 is a part into and from which the first arm part 110 (the first grip part 115) in the manufacturing robot 100 to be described later is inserted and removed. In detail, the first groove part 21 is a part into which the first arm part 110 (the first grip part 115), which is one of a pair of arm parts holding the first battery module 31 in the pre-pressured state to be compressed in the stacking direction X, is inserted and from which the first arm part 110 (the first grip part 115) having removed the pre-pressure to the first battery module 31 is withdrawn.

Similarly, the second groove part 22 is a part into and from which the second arm part 120 (the second grip part 125) in the manufacturing robot 100 to be described later is inserted and removed. In detail, the second groove part 22 is a part into which the second arm part 120 (the second grip part 125), which is another one of the pair of arm parts holding the first battery module 31 in the pre-pressured state to be compressed in the stacking direction X, is inserted and from which the second arm part 120 (the second grip part 125) having removed the pre-pressure to the first battery module 31 is withdrawn.

The first groove part 21 communicates with the first opening surface 16, extends vertically with respect to the first opening surface 16, and has a bottomed concave shape in a sectional view parallel to the stacking direction X. Specifically, the first groove part 21 is formed to communicate with the first opening surface 16 and extend toward the side of the bottom surface 11 e. In this embodiment, the first groove part 21 extends from the first opening surface 16 to the bottom surface 11 e (see FIG. 3B).

The first groove part 21 is formed in a concave shape depressed toward one of the sides in the stacking direction X. In this embodiment, the first groove part 21 is formed in the concave shape whose entirety from the first opening surface 16 to the bottom surface 11 e is depressed toward the one of the sides in the stacking direction X. In other words, the first groove part 21 has a bottomed concave shape whose bottom part extends from the first opening surface 16 to the bottom surface 11 e. The first groove part 21 is formed so that the first arm part 110 (the first grip part 115) can be inserted, and as a concave having a depth (length of the stacking direction X) and a width (length of the width direction Y) so that the first arm part 110 (the first grip part 115) that is rotationally driven to remove the pre-pressure to the first battery module 31 can be withdrawn.

In addition, the first groove part 21 is formed between the two rows of the electrodes 41 and 42 in a plan view perpendicular to the first opening surface 16. The first groove part 21 is formed between the row of the first electrodes 41 and the row of the second electrodes 42 in the width direction Y orthogonal to the stacking direction X (see FIG. 3A). In this embodiment, the first groove part 21 is formed at the center in the width direction Y of the first accommodating part 11. Also, a length L1 of the first groove part 21 along the width direction Y is shorter than a length L2 along the width direction Y between the first electrode 41 and the second electrode 42.

The second groove part 22 communicates with the first opening surface 16, extends vertically with respect to the first opening surface 16 and at least partially has a bottomed concave shape in a sectional view parallel to the stacking direction X. In detail, the second groove part 22 is formed to communicate with the first opening surface 16 and extend toward the side of the bottom surface 11 e. In this embodiment, the second groove part 22 extends from the first opening surface 16 to the bottom surface 11 e (see FIG. 2).

The second groove part 22 is formed in a concave shape depressed toward the other side in the stacking direction X. In this embodiment, the second groove part 22 is formed in the concave shape depressed toward the other side in the stacking direction X from an intermediate position between the first opening surface 16 and the bottom surface 11 e to the bottom surface 11 e. In other words, the second groove part 22 extends from the first opening surface 16 to the bottom surface 11 e, and has a bottomless concave shape from the first opening surface 16 to the intermediate position, and has a bottomed concave shape between the intermediate position and the bottom surface 11 e. The second groove part 22 is formed so that the second arm part 120 (the second grip part 125) can be inserted, and as a concave having a depth (length of the stacking direction X) and a width (length of the width direction Y) so that the second arm part 112 (the second grip part 125) rotationally driven to remove the pre-pressure to the first battery module 31 can be withdrawn.

In addition, the second groove part 22 is formed between the two rows of the electrodes 41 and 42 in a plan view perpendicular to the first opening surface 16. The second groove part 22 is formed between the row of the first electrodes 41 and the row of the second electrodes 42 in the width direction Y orthogonal to the stacking direction X (see FIG. 2). In this embodiment, the second groove part 22 is formed at the center in the width direction Y of the first accommodating part 11. Similar to the first groove part 21, the length of the second groove part 22 along the width direction Y is shorter than the length L2 along the width direction Y between the first electrode 41 and the second electrode 42.

As shown in FIG. 2, a cooling window 29 as a through hole is formed in the fourth inner wall part 11 d of the first accommodating part 11. In a side view, the cooling window 29 has a rectangular shape extending from the side of the first inner wall part 11 a to the side of the second inner wall part 11 b along the stacking direction X. Therefore, in the state in which the first battery module 31 is accommodated in the first accommodating part 11, a part of the side surfaces of all the single battery cells 40 constituting the first battery module 31 is exposed from the cooling window 29. A cooling part through which cooling water flows in the cooling system (not shown) is installed to be in contact with all the single battery cells 40 constituting the first battery module 31 via the cooling window 29. As shown in FIG. 2, in the second accommodating part 12 as well as the third accommodating part 13 and the fourth accommodating part 14, the cooling windows 29 are formed to expose a part of the side surfaces of all the single battery cells 40 constituting the respective battery modules 32, 33, and 34 (the illustration of the cooling windows formed in the third accommodating part 13 and the fourth accommodating part 14 are omitted in FIG. 2).

As will be described in detail later with reference to FIGS. 5A to 5F, the first groove part and the second groove part are parts for insertion and withdrawal of the first arm part 110 and the second arm part 120 at the time of holding the battery module while inserting this battery module into the accommodating part by using the arm parts 110 and 120. Therefore, after the battery module is provided in the accommodating part, the first groove part and the second groove part can be used as the space for accommodating members connected to the battery module.

FIG. 4 is a view showing an installation example of a cell voltage sensor unit 8 which is one of the members connected to the first battery module 31. The cell voltage sensor unit 8 includes a sensor body 81 having a plate shape and extending along the stacking direction on the upper surface of the first battery module 31, and a terminal block 82 on which an output terminal extending from the sensor body 81 is installed. FIG. 4 shows a case in which the terminal block 82 of the cell voltage sensor unit 8 connected to the first battery module 31 is provided in the second groove part 22, but the disclosure is not limited thereto. In the second groove part 22, in addition to the terminal block 82, the sensor body 81, a connector, a bus bar, etc. may also be provided. Further, the above-described members may be provided in the first groove part 21, instead of the second groove part 22, or be provided in both the first groove part 21 and the second groove part 22.

Subsequently, a manufacturing method of the power supply apparatus 1 in this embodiment will be described with reference to FIGS. 5A to 5E. Specifically, a method of accommodating the first battery module 31 in the first accommodating part 11 by using the manufacturing robot 100 having the first arm part 110 and the second arm part 120 will be described.

FIG. 5A is a diagram showing a state in which the first arm part and the second arm part apply the pre-pressure force while gripping the battery module. FIG. 5B is a view showing a state in which the first arm part and the second arm part are inserted into the first groove part and the second groove part from the opening surface side while gripping the battery module. FIG. 5C is a view showing a state in which the pre-pressure force applied by the first arm part and the second arm part is removed. FIG. 5D is a view showing a state in which rotational driving and the pre-pressure force of the first arm part are removed. FIG. 5E is a view showing a state in which the first arm part and the second arm part are withdrawn from the first groove part and the second groove part.

As shown in FIG. 5A, the manufacturing robot 100 has the first arm part 110 and the second arm part 120. The first arm part 110 has a first base part 111, a rotational driving part 112, a first intermediate part 113, and the first grip part 115. The second arm part 120 has a second base part 121, a rotational driving part 122, a second intermediate part 123, and the second grip part 125. The first arm part 110 and the second arm part 120 are vertically moved by a driving part (not shown), and are moved to open and close so as to change the distance with respect to each other. In addition, the first arm part 110 and the second arm part 120 are configured to make the first grip part 115 and the second grip part 125 rotatable by the rotational driving parts 112 and 122.

First, as shown in FIG. 5A, the manufacturing robot 100 clamps the first battery module 31 by using the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120. The manufacturing robot 100 grips the first battery module 31 while applying a pre-pressure force along the stacking direction X to the first end part 31 a and the second end part 31 b by using the first grip part 115 and the second grip part 125. At this time, as shown in FIG. 5A, the first grip part 115 and the second grip part 125 grip the first battery module 31 by using the first grip part 115 and the second grip part 125, so as to contact the first battery module 31 from an upper surface 31 c to a lower surface 31 d at the first end part 31 a and the second end part 31 b. As a result, the first battery module 31 is slightly compressed along the stacking direction X.

Subsequently, as shown in FIG. 5B, in the state of applying the pre-pressure force while gripping by using the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120, the manufacturing robot 100 inserts the first battery module 31 into the first accommodating part 11 from the side of the first opening surface 16. In the state of applying the pre-pressure force while gripping by using the first grip part 115 and the second grip part 125, the manufacturing robot 100 inserts the first grip part 115 into the first groove part 21 from the side of the first opening surface 16 and inserts the second grip part 125 into the second groove part 22 from the side of the first opening surface 16.

Subsequently, as shown in FIGS. 5C and 5D, the manufacturing robot 100 removes the pre-pressure force applied to the first battery module 31 by the first grip part 115 and the second grip part 125. In particular, the manufacturing robot 100 rotationally drives the rotational driving part 112 in the first arm part 110 in the direction of an arrow R1 to rotationally drive the first grip part 115 in the direction of an arrow K1, and rotationally drives the rotational driving part 122 of the second arm part 120 in the direction of an arrow R2 to rotate and drive the second grip part 125 in the direction of an arrow K2.

As a result, the first grip part 115 and the second grip part 125 are separated from the first battery module 31. The first battery module 31 from which the pre-pressure force is removed deforms so that the end parts 31 a and 31 b respectively move to the side of the first inner wall part 11 a and the side of the second inner wall part 11 b in the stacking direction X. Then, due to the holding load generated between the first end part 31 a and the first inner wall part 11 a and the holding load generated between the second end part 31 b and the second inner wall part 11 b, the first battery module 31 is held in the compressed state in the first accommodating part 11.

Subsequently, as shown in FIG. 5E, the manufacturing robot 100 withdraws the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120 from the first groove part 21 and the second groove part 22.

Subsequently, as shown in FIG. 5F, the cell voltage sensor unit 8 is connected to the first battery module 31. Specifically, the sensor body 81 extending along the stacking direction is provided on the top surface of the first battery module 31, a plurality of terminals (not shown) extending from the sensor body 81 are connected to the electrodes of each of the single battery cells constituting the first battery module 31, and the terminal block 82 provided on the stacking direction end part side of the sensor body 81 is installed in the second groove part 22. As a result, the first battery module 31 is accommodated directly in the first accommodating part 11, and the power supply apparatus 1 of this embodiment is manufactured.

According to this embodiment, the following effects are obtained. (1) The power supply apparatus 1 includes the enclosure 10 in which the first accommodating part 11 being in a trough shape and having the first opening surface 16 is formed, and the first battery module 31 held in the first accommodating part 11. In the first inner wall part 11 a and the second inner wall part 11 b on the two end sides in the stacking direction X of the first battery module 31 in the first accommodating part 11 of the enclosure 10, the first groove part 21 and the second groove part 22 which respectively communicate with the first opening surface 16, extend perpendicularly with respect to the first opening surface 16, and have a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction X are formed. Also, due to the holding loads acting between the first end part 31 a and the second end part 31 b on the two end sides in the stacking direction X and the first inner wall part 11 a and the second inner wall part 11 b, the first battery module 31 is held in the first accommodating part 11. According to the power supply apparatus 1, the first battery module 31 can be mounted directly in the first accommodating part 11 of the enclosure 10 in a state of being compressed along the stacking direction X without using a holder, etc., for applying a load to the first battery module 31 along the stacking direction X. In order to mount the first battery module 31 in the first accommodating part 11 as described above, it is necessary to use the first arm part 110 and the second arm part 120 provided on the two end sides in the stacking direction X of the first battery module 31, and accommodate the first battery module 31 together with the first arm part 110 and the second arm part 120 in the first accommodating part 11 while applying the pre-pressure force along the stacking direction X. With respect to this, according to the power supply apparatus 1, the first groove part 21 and the second groove part 22 formed in the first inner wall part 11 a and the second inner wall part 11 b serve as escape grooves of the first arm part 110 and the second arm part 120, so the first battery module 31 can be mounted directly in the first accommodating part 11 of the enclosure 10 in the state of being compressed along the stacking direction X.

Further, according to this embodiment, the power supply apparatus 1 has the first groove part 21 and the second groove part 22 into which the first grip part 115 of the first arm part 110 and the second grip part 125 of the second arm part 120 can be inserted in the state of applying the pre-pressure force to the first battery module 31, and which can be rotationally driven to remove the pre-pressure force. As a result, the power supply apparatus 1 can directly accommodate the first battery module 31 in the first accommodating part 11 by using the manufacturing robot in the state in which the pre-pressure force is applied.

Further, according to this embodiment, in the power supply apparatus 1, the first battery module 31, the second battery module 32, the third battery module 33, and the fourth battery module 34 are directly mounted in the enclosure 10. Accordingly, the volume energy density is improved in the power supply apparatus 1. Also, in this way, the parts used in the power supply apparatus 1 can be reduced. Moreover, with the parts used being reduced, the product cost of the power supply apparatus 1 can be reduced, and the overall weight of the power supply apparatus 1 can also be reduced. Furthermore, in this way, the overall volume of the power supply apparatus 1 can also be reduced.

(2) In the power supply apparatus 1, the first groove part 21 and the second groove part 22 extend from the first opening surface 16 to the bottom surface 11 e of the first accommodating part 11. Therefore, according to the power supply apparatus 1, the escape grooves of the first arm part 110 and the second arm part 120 can be secured from the first opening surface 16 to the bottom surface 11 e of the first accommodating part 11. Hence, according to the power supply apparatus 1, the pre-pressure force applied to the first battery module 31 can be uniform because the first arm part 110 and the second arm part 120 extending from the upper surface 31 c to the lower surface 31 d of the first battery module 31 can be used when the pre-pressure force is applied along the stacking direction X of the first battery module 31.

(3) In the power supply apparatus 1, the first battery module 31 is provided in the first accommodating part 11, so that the two electrodes 41 and 42 of each of the single battery cells 40 are arranged in rows along the stacking direction X in a plan view, and the first groove part 21 and the second groove part 22 are formed between the two rows of electrodes in a plan view. Therefore, in the first battery module 31 accommodated in the first accommodating part 11, since the loads along the stacking direction X can be applied to the two electrodes 41 and 42, which are portions where the first groove part 21 and the second groove part 22 are not formed, the occurrence of troubles in the respective electrodes 41 and 42 of the first battery module 31 during charge and discharge can be suppressed.

(4) In the power supply apparatus 1, the terminal block 82 as a component of the cell voltage sensor unit 8 connected to the first battery module 31 is provided in the second groove part 22 serving as the escape groove of the second arm part 120 when the first battery module 31 is accommodated in the first accommodating part 11. Thus, according to the power supply apparatus 1, the volume of the enclosure 10 can be reduced.

It should be noted that the disclosure is not limited to the above embodiments, and variations, improvements, etc. within the scope of achieving the objective of the disclosure are included in the disclosure. 

What is claimed is:
 1. A power supply apparatus, comprising: an enclosure in which an accommodating part being in a trough shape and having an opening surface is formed; and a battery module which is in a column shape and in which a plurality of single battery cells are stacked, wherein the battery module is held in the accommodating part by holding loads acting between a first end part and a second end part on two end sides in a stacking direction and a first inner wall part and a second inner wall part opposite to each other in the accommodating part, and a first groove part is formed in the first inner wall part, a second groove part is formed in the second inner wall part, the first groove part and the second groove part communicate with the opening surface, extend perpendicularly with respect to the opening surface, and have a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction respectively.
 2. The power supply apparatus according to claim 1, wherein the first groove part and the second groove part extend from the opening surface to a bottom surface of the accommodating part.
 3. The power supply apparatus according to claim 2, wherein the battery module is provided in the accommodating part, such that two electrodes of each of the single battery cells are arranged in rows along the stacking direction in a plan view, and the first groove part and the second groove part are formed between two rows of the electrodes in the plan view.
 4. The power supply apparatus according to claim 1, wherein the battery module is provided in the accommodating part, such that two electrodes of each of the single battery cells are arranged in rows along the stacking direction in a plan view, and the first groove part and the second groove part are formed between two rows of the electrodes in the plan view.
 5. The power supply apparatus according to claim 4, wherein at least one of the first groove part and the second groove part is provided with a member connected to the battery module.
 6. The power supply apparatus according to claim 3, wherein at least one of the first groove part and the second groove part is provided with a member connected to the battery module.
 7. The power supply apparatus according to claim 2, wherein at least one of the first groove part and the second groove part is provided with a member connected to the battery module.
 8. The power supply apparatus according to claim 1, wherein at least one of the first groove part and the second groove part is provided with a member connected to the battery module.
 9. A method for manufacturing a power supply apparatus, the power supply apparatus comprising: an enclosure in which an accommodating part being in a trough shape and having an opening surface is formed; and a battery module which is in a column shape and in which a plurality of single battery cells are stacked, wherein the battery module is held in the accommodating part by holding loads acting between a first end part and a second end part on two end sides in a stacking direction and a first inner wall part and a second inner wall part opposite to each other in the accommodating part, and a first groove part is formed in the first inner wall part, a second groove part is formed in the second inner wall part, the first groove part and the second groove part communicate with the opening surface, extend perpendicularly with respect to the opening surface, and have a bottomed or bottomless concave shape in a sectional view parallel to the stacking direction respectively, the method comprising: clamping the battery module by using a first arm part and a second arm part, and gripping the battery module while applying a pre-pressure force along the stacking direction to the first end part and the second end part; inserting the first arm part and the second arm part into the first groove part and the second groove part from the opening surface side in a state in which the battery module is gripped by using the first arm part and the second arm part; and withdrawing the first arm part and the second arm part from the first groove part and the second groove part after removing the pre-pressure force applied by the first arm part and the second arm part.
 10. The method of manufacturing a power supply apparatus according to claim 9, further comprising providing a member connected to the battery module in at least one of the first groove part and the second groove part after withdrawing the first arm part and the second arm part from the first groove part and the second groove part. 